Sample machining device and sample analysis device

ABSTRACT

The invention relates to a sample machining device, in particular for preparing samples for OES and/or XRF and/or combustion analyses, having at least one sample holder, and to provide a development which is advantageous in use proposes that the machining device includes a cylindrical milling cutter, the cylindrical milling cutter and the sample holder being movable relative to one another in such a manner that a sample which can be held in the sample holder can be divided by means of the cylindrical milling cutter to produce a free piece and a remainder piece of the sample which can still be held in the sample holder, and that at least one additional tool, in particular a drilling or separate milling tool, is provided in order to produce chips from the remainder piece of the sample. Moreover, the invention relates to a sample analysis device in which, according to the invention, the abovementioned sample machining device and means for carrying out OES analysis and/or XRF analysis and/or combustion analysis are provided.

This application claims priority of pending German Patent ApplicationNo. 20 2004 015 484.6 filed on Oct. 4, 2004.

The invention relates to a sample machining device, in particular forpreparing samples for OES and/or XRF and/or combustion analyses, havingat least one sample holder.

Sample machining devices of the type mentioned in the introduction areknown. They have a cutting disk. In this way, a sample which has beeninserted into the sample holder and is, for example, in the shape of acone is divided at 90 degrees to the longitudinal axis approx. 20 to 25mm below the smaller end face. With regard to further samplepreparation, it is known to grind the upper part of the sample on agrinding machine for a subsequent possible OES analysis, while a disk,for example with a thickness of approx. 4 mm is cut from the lower partof the sample. This disk is placed into a stamp and in this way samplepieces with a diameter of likewise 4 mm are stamped out of the disk. Thestamped pieces are then pneumatically transported to combustionanalyzers for detecting carbon (C), sulfur (S), nitrogen (N) and oxygen(O). Therefore, to prepare the samples for subsequent analyses, theknown sample machining device requires additional means and a series offurther working steps. An additional factor is that in particular inthis context there is a risk of the fresh, i.e. particularly pure, metalsurface required for the analyses being contaminated by constituents ofthe air, thereby reducing their suitability for the investigations.

Proceeding from this, the invention is based on the object of developinga sample machining device of the type mentioned in the introduction in amanner advantageous for use such that the abovementioned drawbacks areas far as possible avoided.

According to the invention, this object is achieved first and foremostby virtue of the fact that the sample machining device includes acylindrical milling cutter, the cylindrical milling cutter and thesample holder being movable relative to one another in such a mannerthat a sample which can be held in the sample holder can be divided, inthe state held therein, by means of the cylindrical milling cutter toproduce a free piece of the sample and a remainder piece of the samplewhich can still be held in the sample holder, and that at least oneadditional tool, in particular a drilling or separate milling tool, isprovided in order to produce chips from the remainder piece of thesample. Suitable samples are preferably metal samples, for example castsamples and the like. The cylindrical milling cutter is such that it issuitable for dividing the sample and achieving clean machined surfaceson the pieces formed in the same operation. A sample machining device ofthis type advantageously on the one hand ensures that the cutting of thesample into pieces, at a freely removable piece which is thereby formed,leads directly, i.e. immediately, to a clean machined surface which issuitable for subsequent investigations, in particular OES and/or XRFinvestigations, so that there is no need for any subsequent remachining,such as for example grinding.

The invention also achieves improvements with regard to the preparationof the sample remainder piece. The latter, after the dividing operationby means of the cylindrical milling cutter, such that it likewise has acorrespondingly clean machined surface as a result of the millingoperation, can directly remain in the sample holder and can then bemachined further therein. According to the invention, an additionaltool, in particular a drilling or separate milling tool, is for thispurpose used to produce chips from the remainder piece of the sample,which chips are suitable, for example, for carrying out combustionanalyses. Compared to the abovementioned prior art, the sample machiningdevice according to the invention achieves time-saving machining of thesamples and in particular allows a high quality of preparation for OESand/or XRF and/or combustion analyses. In this context, the abbreviationOES, which is known per se, stands for optical emission spectrometry(optical emission spectroscopy) and the abbreviation XRF stands forX-ray fluorescent spectrometry (X-ray fluorescence spectroscopy).

It is preferably provided that the sample holder can be displaced in thelateral and/or vertical direction at least between machining positionsof the cylindrical milling cutter and of the additional tool. As analternative or in combination with this measure, it is possible for thecylindrical milling cutter and/or the additional tool to be displaceablein the lateral and/or vertical direction for the purpose of acorresponding position change and/or to carry out the associatedmachining. A simple structure is made possible by the cylindricalmilling cutter being disposed on a first spindle and the additional toolbeing disposed on a second spindle. Furthermore, it is preferred if thesample holder is adapted to holding rotationally symmetrical samples,the sample center line extending at least substantially parallel to therotation center line of the cylindrical milling cutter. The result ofthis is that the parting plane of the workpiece defined by thecylindrical milling cutter extends at an angle of 90 degrees to thesample longitudinal axis, i.e. perpendicular to the sample longitudinalaxis. A refinement according to which the sample holder is adapted toholding conical samples, so that the wider foot end of the sample isreceived in the sample holder and the narrowing sample section protrudesfrom the sample holder, is also preferred. Alternatively, it is possiblefor the sample holder to be adapted to the reverse form of fixing of thesample, i.e. with the widening section protruding. Conical samples havethe advantage over cylindrical samples of being easier to demold duringproduction in the casting process.

With regard to possible adapting to conical samples, it is alsopreferred if the sample machining device is adapted to receiving conicalsamples, the larger end diameter of which is in the range from 36 to 45mm and/or the smaller end diameter of which is in the range from 28 to36 mm and/or the height of which is in the range from 45 to 65 mm.

According to a further aspect, it is possible to provide control meansfor the in particular automatic centering of the additional tool withrespect to the clamping region of the sample holder. In this case, thecontrol means may suitably be adapted for in particular automaticalignment of the additional tool to the remainder piece of the sample inorder to form chips from a central region of the sample, in particularfrom the center of its surface formed by the cylindrical milling cutter.This makes it possible to remove chips which are unaffected by sampleboundary influences from the interior of the sample, for example inorder for combustion analyses to be carried out. It is also possible forthe milling cutter or drill provided as the additional tool to bespecifically adapted to forming and removal of chips from the surface ofthe remainder piece.

According to a further aspect of the invention, it is possible for thesample machining device to have a purge device for supplying inert gas,in particular argon (Ar), helium (He), nitrogen (N₂) or the like, to atleast one milling and/or drilling region of the sample machining device.This makes it possible to purge the machining regions of cylindricalmilling cutter and/or additional tool with inert gas flowing over them,so that contamination by air elements is avoided at the metallicallypure surfaces formed on the sample or sample parts, with the result thatbetter conditions are obtained for subsequent analyses. As analternative to or in combination with this measure, it is possible foran extraction device for sucking out chips that are to be produced bymeans of the additional tool to be provided at the sample machiningdevice. An extraction device of this type provides the advantage that onthe one hand continuous removal of chips and therefore uniform machiningconditions are obtained and, moreover, short transport times arepossible for the chips, for example to an analysis device, such as acombustion analyzer or the like. An expedient refinement is consideredto reside in the extraction device having at least one transport fanwhich sucks the inert gas out of the at least one milling and/ordrilling region as carrier gas for the chips in the extraction device.The result of this is that the inert gas even during transport stillmaintains protection for the chips against contamination fromconstituents of the air, so that the chips can be fed to an analysisdevice with a high level of purity.

Moreover, the invention relates to a sample analysis device which has atleast one sample machining device according to one or more of thefeatures explained above and at which sample analysis device means forcarrying out OES analysis and/or XRF analysis and/or combustion analysisare provided. For analyses to be carried out, a sample analysis deviceof this type allows prior, preparatory machining of samples and thenimmediately afterwards allows the analysis (analyses) itself/themselvesto be carried out on freshly machined sample material of a high quality.Spectrometers or spectroscopes which are known per se are suitable forthe OES and/or XRF analysis. The sample analysis device may haveconveying means which are adapted to transporting the free piece of thesample which has been cut off by the cylindrical milling cutter to thesaid means in order for the OES and/or XRF analysis to be carried out.The transport means of this type used may, for example, be conveyorbelts, a tube post system or similar application. In addition, it ispossible to provide automated handling means, for example for loadingthe conveying means and/or introducing the piece which has been cut offinto the spectrometer or spectroscope.

As an alternative or in combination, the sample analysis device may havea number of thermal analyzers, which are preferably adapted fordetecting carbon (C), sulfur (S), nitrogen (N) and/or oxygen (O). In thesample analysis device according to the invention, these analyzers canpreferably be used to examine the chips produced from the remainderpiece of the sample by means of the additional tool of the samplemachining device. To continuously and quickly transport the chips fromthe sample machining device to the thermal analyzers, the sampleanalysis device may have means for pneumatically transporting chips. Inthis context, in particular the extraction device may be adapted fortransporting chips and inert gas as carrier gas for the chips from thesample machining device to the thermal analyzers. The chips and theinert gas may, for example, be transported from the sample machiningdevice to the analyzers in a pipeline under the influence of a pressuredrop effected by the transport fan.

A method for using the sample machining device according to theinvention which is included by the invention is as follows: a forexample conical sample, preferably a metal sample, more preferably acast sample, is placed into a sample holder of the sample machiningdevice and divided using the cylindrical milling cutter of this device.The upper piece, i.e. the piece remote from the sample holder, of thesample is finished, i.e. it already has the surface which it requiresfor a subsequent possible OES and/or XRF analysis. The lower part of thesample is still located in the sample holder of the sample machiningdevice. The sample holder, with this remainder piece of the sample heldin it, is moved to beneath an additional tool, preferably a drill or aspecial milling head, which is preferably secured to a second spindle.The additional tool drills out or removes chips from the sample bodyheld in the sample holder, preferably from the center of the samplebody. In a preferred realization of the method, the chips are sucked outby means of an extraction device and are preferably transported onwardspneumatically. According to a likewise preferred refinement of themethod, at least one drilling and/or milling region of the samplemachining device is purged with inert gas flowing over it, so thatcontamination of sample material by air elements is avoided. The methodfor using the sample machining device or sample analysis deviceaccording to the invention is preferably carried out in such a mannerthat the free piece which has been cut off the sample by means of thecylindrical milling cutter, after it has been cut off, is transporteddirectly to analysis devices, which are preferably suitable for carryingout OES and/or XRF analysis. With regard to the chips produced by theadditional tool, it is preferred for these chips to be transportedpneumatically to thermal analyzers. The extraction device canexpediently be used for this purpose. This extraction device can suckout the inert gas which has been purged onto the at least one millingand/or drilling region by means of a transport fan, and this inert gascan then be used as carrier gas for passing the chips to the thermalanalyzers.

All features disclosed are (inherently) pertinent to the invention. Thedisclosure content of the associated/appended priority documents (copyof the prior application) is hereby incorporated in its entirety in thedisclosure of the application, partly with a view to incorporatingfeatures of these documents in claims of the present application.

1. Sample machining device, in particular for preparing samples for OESand/or XRF and/or combustion analyses, having at least one sampleholder, characterized in that the machining device includes acylindrical milling cutter, the cylindrical milling cutter and thesample holder being movable relative to one another in such a mannerthat a sample which can be held in the sample holder can be divided bymeans of the cylindrical milling cutter to produce a free piece and aremainder piece of the sample which can still be held in the sampleholder, and in that at least one additional tool, in particular adrilling or separate milling tool, is provided in order to produce chipsfrom the remainder piece of the sample.
 2. Sample machining deviceaccording to claim 1, characterized in that the sample holder can bedisplaced in the lateral and/or vertical direction at least betweenmachining positions of the cylindrical milling cutter and of theadditional tool.
 3. Sample machining device according to claim 1,characterized in that the cylindrical milling cutter is disposed on afirst spindle and the additional tool is disposed on a second spindle.4. Sample machining device according to claim 1, characterized in thatthe sample holder is adapted to holding rotationally symmetricalsamples, so that the sample center line extends at least substantiallyparallel to the rotation center line of the cylindrical milling cutter.5. Sample machining device according to claim 1, characterized in thatthe sample holder is adapted to holding conical samples, so that thewider foot end of the sample is received in the sample holder and thenarrowing sample section protrudes from the sample holder.
 6. Samplemachining device according to claim 1, characterized in that the samplemachining device is adapted to receiving conical samples, the larger enddiameter of which is in the range from 36 to 45 millimeters and/or thesmaller end diameter of which is in the range from 28 to 36 millimetersand/or the height of which is in the range from 45 to 65 millimeters. 7.Sample machining device according to claim 1, characterized in thatcontrol means are provided for the in particular automatic centering ofthe additional tool with respect to the clamping region of the sampleholder.
 8. Sample machining device according to claim 1, characterizedin that the control means are adapted for in particular automaticalignment of the additional tool to the remainder piece in order to formchips from a central region, in particular from the center of itssurface formed by the cylindrical milling cutter.
 9. Sample machiningdevice according to claim 1, characterized in that the milling cutter ordrill provided as additional tool is adapted for removal of chips fromthe surface of the remainder piece.
 10. Sample machining deviceaccording to claim 1, characterized in that a purge device for supplyinginert gas, in particular argon, helium or nitrogen, into at least onemilling and/or drilling region of the sample machining device isprovided.
 11. Sample machining device according to claim 1,characterized in that an extraction device for sucking out chips thatare to be produced by means of the additional tool is provided. 12.Sample machining device according to claim 1, characterized in that theextraction device has at least one transport fan which sucks the inertgas out of the at least one milling and/or drilling region as carriergas for the chips.
 13. Sample analysis device, characterized in that atleast one sample machining device according to claim 1 is provided, andin that means for carrying out OES analysis and/or XRF analysis and/orcombustion analysis are provided.
 14. Sample analysis device accordingto claim 13, characterized in that conveying means are provided fortransporting the free piece of the sample from the sample machiningdevice to the means for carrying out the OES analysis and/or XRFanalysis.
 15. Sample analysis device according to claim 14,characterized in that a number of thermal analyzers are provided, inparticular adapted for detecting carbon, sulfur, nitrogen and oxygen.16. Sample analysis device according to claim 15, characterized in thatmeans for pneumatically transporting chips from the sample machiningdevice to the thermal analyzers are provided.
 17. Sample analysis deviceaccording to claim 16, characterized in that the extraction device isadapted for transporting chips and inert gas as carrier gas from thesample machining device to the thermal analyzers.